Enantioselective Biotransformation of Prochiral Ketone via Daucus carota Ryan Smith, Charlie Knox, and Elizabeth Davis
Faculty Advisor: Dr. Michele Harris Department of Chemistry
Stephen F. Austin State University
Incubated carrots with ketone, extracted alcohol product, measured optical activity, and verified product using IR spectroscopy.
Incubated carrot strips in buffer with low percent detergent . Used ammonium sulfate precipitation. Analyzed both supernatant and pellet using SDS-PAGE.
Placed known quantity of purified alcohol on disk and placed on a Petri dish growing bacteria.
Biotransformations of prochiral ketones can be performed using plant cells. The benefits of using plant cells include low cost, environmentally sound procedures compared to conventional chemical processes, and the stereospecific nature of the reaction.1,2
Benzofuran-2-yl methyl ketone was reduced to (-)-benzofuran-2-yl-ethanol after incubation with carrots in water. The reaction was enantioselective in that it produced the S-isomer as indicated by optical activity. Currently, attempts to isolate the carrot enzyme and antimicrobial studies of the (-)-benzofuran-2-yl-ethanol product are underway.
SDS-PAGE Results
Funding for this project was provided by the Robert A. Welch Departmental Grant (AN-0008) and from SFASU Office of Research and Sponsored Programs Faculty Research Grant
1. Ravia, S. et.al. J.Chem.. 2006, 83, 1049-1051
2. Yadav, J.S.; et.al. J. Org. Chem., 2002, 67, 3900-3903
3. Yang, Z.; et.al. J. Micro. Biotech., 2008, 35, 1047-1051
Abstract Methods
References
Antibacterial Results
Funding
Reaction
Possible Reaction Pathway
ST
D
10 µ
l R
S
10 µ
l S
N
Bla
nk
Bla
nk
5µl
RS
50%
5µl
SN
50%
739.
60
803.
4487
8.92
941.
4610
05.6
8
1022
.22
1073
.48
1152
.80
1172
.12
1253
.29
1300
.84
1453
.85
3349
.33
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
%T
500 1000 1500 2000 2500 3000 3500 4000
Wavenumbers (cm-1)
Optical Activity Results
The optical activity of the alcohol product agreed with literature values of -16.4 and the percent yield was 37%.
IR Spectroscopy Results
Ketone
Alcohol
Ring of inhibition of bacterial growth. The concentration of the alcohol was 1.5 mg/ml.
Arrows indicate protein bands isolated from carrot surface.
Acknowledgements
The following students collaborated on this project: Betty Abraha, Adrianne Crandall, Natasha Impink Hernandez, Olivia Korpe, John Sharp, and Kenneth Smith.
Conclusions
This undergraduate group effort has worked out the preliminaries for: isolating pure, optically active alcohol demonstrated carrot protein can be
removed from surface of carrot, and the alcohol may some antibacterial
properties at fairly high concentrations.